Ray-Triangle Intersection
Developed with Ben Trumbore from Cornell University. The
source is here.
I also have some extra optimizations
for this and some
extra statistics for different CPUs.

Triange-Triangle Overlap Test [Updated 2001-06-20]
The original source code is here.
I have optimized (in that I replaced the divisions
with some multiplications - from a suggestion by
Dave Eberly) that code since
then.
New (faster) code is
here. If you want the line of intersection as well, the get
this code.

Triangle-Box Overlap Test [Updated 2004-08-25] Old code is here.New, faster code is here. It's not noticably faster on a 1333 MHz PC,
but it's about 15% faster on a SUN 333MHz.Bug-fixed code This is the code you should get. It correctly
reports intersections for triangles completely in a box plane. Bug fix by Nick Pelling: thanks!